(1. 中南大学 物理科学与技术学院， 长沙 410075;
2. 中山大学 光电材料与技术国家重点实验室， 广州 510275)
摘 要: 采用溶胶-凝胶法制备了纳米晶La1-xSrxMnO3， 运用场发射扫描电镜（FESEM）、 X射线衍射分析仪（XRD）和红外光谱分析仪（FTIR）等手段对掺杂样品的微结构、 形貌等进行了分析。 结果表明： 当掺杂浓度x为0～0.5时， 所制备的粉体为单一钙钛矿相； 不同的掺杂浓度和热处理温度会使样品的晶格参数发生显著变化；La1-xSrxMnO3纳米晶粒子尺寸为10～80 nm； 掺杂浓度和热处理条件对样品粒子尺寸产生很大的影响， 在相同的热处理条件下，掺杂浓度高的样品晶粒尺寸较小， 且掺杂浓度的增大会引起晶粒特征红外振动的红移和宽化现象。
关键字: 纳米晶； 溶胶-凝胶； 钙钛矿； 晶格参数
（1. School of Physics Science and Technology,
Central South University, Changsha 410075, China；
2. State Key Laboratory of Optoelectronic Materials and
Technology, Zhongshan University, Guangzhou 510275, China）
Abstract: Nanocrystalline La1-xSrxMnO3 powders were prepared by sol-gel process. The structure and particle-size of the powders were controlled by adjusting the annealing temperature. The morphologies and microstructures of the powders were analyzed by field emission scanning electron microcopy (FESEM), X-ray diffractometry(XRD) and Fourier-transformed infrared spectroscopy(FTIR). The results show that La1-xSrxMnO3 is single perovskite structure if doped concentration x is 0-0.5. The crystal lattice parameters of the sample are changed obviously with the change of doped concentration and annealing temperature. The particle-size of the powders is 10-80 nm and influenced greatly by the doped concentration.At the same annealing temperature, the higher doped concentration is, the smaller particle-size of the powders is. The concentration increase of doped ion will make the characteristic infrared absorb peaks to shift to higher warenumber and broader frequencies.
Key words: nanocrystalline; sol-gel; perovskite; crystal lattice parameters
